1. Technical Field
This disclosure relates to integrated circuit design and fabrication. More specifically, this disclosure relates to methods and apparatuses for efficiently and accurately computing extreme ultraviolet (EUV) lithography shadowing effect.
2. Related Art
Extreme ultraviolet (EUV) lithography is one of the leading technologies for 16 nm and smaller node device patterning. An important patterning issue in EUV lithography is the shadowing effect due to oblique illumination. This effect can cause CD errors up to a few nanometers. Therefore, this effect needs to be compensated during mask synthesis.
Inaccuracies in the process model negatively affect the efficacy of downstream applications. For example, inaccuracies in a process model can reduce the efficacy of resolution enhancement technologies (RETs). If the process model is computationally inefficient, it can increase the time-to-market for an integrated circuit, which can cost millions of dollars in lost revenue.